The archaebacteria of extreme saline habitat.

Options

A. are able to use chemical energy for food synthesis
B. are called halophiles
C. oxidise sulphur to sulphuric acid under aerobic conditions
D. are obligate anaerobes

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about archaebacteria that thrive in extreme saline habitats. We need to identify the specific term used to describe these organisms.

2. **Analyzing the Options**:
- **Option 1**: "Are able to use chemical energy for food synthesis." This statement is incorrect because it does not specifically refer to archaebacteria in saline environments.
- **Option 2**: "Are called halophiles." This option is relevant as halophiles are organisms that thrive in high salt concentrations, which fits the description of archaebacteria found in extreme saline habitats.
- **Option 3**: "Oxidize sulfur to sulfuric acid under aerobic conditions." This statement is also incorrect as it does not pertain to saline environments.
- **Option 4**: "Obligate Anaerobes." This option is incorrect because obligate anaerobes are organisms that cannot survive in the presence of oxygen, which does not relate to saline habitats.

3. **Conclusion**: Based on the analysis, the correct answer is that the archaebacteria of extreme saline habitats are called **halophiles**.

### Final Answer:
The archaebacteria of extreme saline habitats are called **halophiles**.

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